Apparatus for package reinforcement using molding underfill

An apparatus comprising:

• a first substrate having a first side and a second side;
• a plurality of electrical connections formed on the second side of the first substrate;
• a second substrate electrically coupled to the plurality of electrical connections;
• a molding compound on the second side of the first substrate, wherein the plurality of electrical connections extend through the molding compound;
• and
• a molding underfill interposed directly between the molding compound and the second substrate, wherein the molding underfill encapsulates less than all of the plurality of electrical connections.

A device comprising:

• a first substrate having a first side and a second side, the second side being opposite the first side;
• a plurality of electrical connections formed on the second side of the first substrate;
• a second substrate electrically coupled to the plurality of electrical connections;
• a molding compound on the second side of the first substrate, the plurality of electrical connections extending through the molding compound;
• and
• a molding underfill between the molding compound and the second substrate in a first region of the device, wherein there is substantially no molding underfill between the molding compound and the second substrate in a second region of the device.